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amount of water or increase of speed in this Turning from the mantle of drift to conpoten the stream may out a gorge in the sideration of the solid rock beneath, one

nuk plain 11 had previously formed and finds that it calls for only a further applicaleave the immer plain terraced above its tion of the principles which have just been Walets. These are but a few of the obser considered. A large proportion of the rocks Tabela which may be made upon almost of the earth's crust are made up of layers or ani ninmng stream and which will be seen strata showing deposition by water and un pull and interpret the behavior of all hence called stratified rocks. An area of silvians and rivers

sandstone differs from a bed of sand simply listening an the effect of the conti- in being more firmly consolidated either by hoitol me shine and its dejuevits it may be cementing waters or the pressure of overson that ple's slaloms vi drainage must lving lavers

lving lavers. The bank of drift reprehann by the ting senrad in the cut previously noted would,

fuath's Tills and as and that if cinselated into rock, form what is 1* W ventes have been known as a conglomerate or pudding stone.

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may be able to make on the outcrops met, it will usually be found when the survey of the area is finished, that some system or course of arrangement of the rocks has been discovered, such as is exhibited by the series of Ms in the accompanying cut. When the formations are thus mapped further study in detail can be given each particular one. In all such observations one should, of course, be careful to distinguish the rock in place from what may be simply boulders protruding through the soil and having no connection with the rock be

neath. INCLINED STRATA, NEW YORK.

Further, care should be used to distin

guish effects of erosion from those of upturned over. Such dislocations must come

lift. The carving of most of the prominent from earth movements of greater or less

features in a locality, say a mile square, extent, which also caused fracturing and

will be the result of erosion which has fissuring. In such earth movements some

worn away the softer portions and left the strata would go up, others down, and vari- harder standing in relief rather than the ous readjustments would take place. Such pushing upward of the higher portions by dislocations are always more extensive and

some force acting beneath. violent in a mountain region and here,

It would be impracticable to give here therefore, is the greater opportunity for directions which would enable one to disfinding valuable mineral deposits, since the tinguish in the field minerals of economic fracturing and fissuring affords facilities value. Appearances to the untrained eye for the movement of hot waters in which are usually misleading, the most showy spegold and other metals may be held and cies being in general the least valuable for by which they are laid down.

economic purposes. Thus the brass yelIn seeking to follow any given rock for low pyrite, worthless when only dissemimation through a region, the mantle of soil nated in small grains, is often mistaken for and vegetation or the presence of forests gold, and even scales of glittering mica and bodies of water to a large extent hide appearing yellow in the sunlight, were shipthe underlying rock from view in any but ped in quantities to England as gold, by the a desert country.

To overcome this diffi- early explorers of Virginia. The vast maculty the geologist must learn to take advantage of all exposures, or "outcrops," as

Sec. 17, T. 44.N., R.10W. they are called, and draw his conclusions from them.

m Every railroad cut or excavation for highways, every quarry or even diggings for the foundations of buildings, every well, bored or dug, will afford clues which he must use to the utmost to enable him to trace out the order of the rock formations. Even if the country is uninhabited so that no such aids are at liand, a considerable knowledge may be gained by a systematic reconnaissance. This may be carried on after the method adopted by goyernmental surveys illustrated in the accompanying sketch

This represents a plot of a given area, over which are drawn imaginary north and south lines at equal di tances. If, now, one paces over the area, following these lines in succession and marking in his notebook (in which the area is thus plotted) all the observations he

DIAGRAM ILLUSTRATING MANNER OF MAKING

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RECONNAISSANCE SURVEY.

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jority of profitable gold ores, if the placer preserved to a certain extent, but the
or stream ores be excepted, can be said to chances of their ever being replaced by
exhibit no gold whatever to the naked eye. mineral matter and so of becoming truly
In general, minerals likely to prove of value petrified are exceedingly few.
as ores, are opaque and have what is called The parts then of living animals which
metallic luster, although there are impor are preserved as fossils and from which
tant exceptions to this rule. Color is a our knowledge of them is drawn are such
criterion of very little value, unless intelli as were composed of mineral matter in life,
gently used, as the same mineral may ap and include bones and teeth of vertebrates
pear of various colors, and the quantity of and the shells and internal skeletons of
an ingredient required to color a mineral mollusks, corals, etc. Actual fossils may
mas: is very small.

also consist of casts or impressions show-
The pebbles found on beaches and in ing the form of the living animal or plant
streams largely consist of some form of which has been preserved by the mud in
quartz, since this mineral is hard and is left which the object was buried.
behind after its associated rock is

A form of mineral aggregate which is away. The different colors of these peb- easily liable to be mistaken for a petrifacbles are due generally to staining by iron tion is that known as a concretion. These in various stages of oxidation.

may be formed in soils of all kinds, but When pebbles of peculiar form are found it should be remembered that such forms may be given by differences in the resistance to wear by the different minerals

of which the pebble is composed, and that only in the rarest instances can they be "petrified” objects. Petrifaction as the term is generally understood, i. e., meaning a once living substance, "turned" to stone, almost never takes place in Nature. The processes of decay are too rapid and the conditions permitting deposit of mineral substances too rare to allow such occur PINNACLES 350 FEET HIGH PRODUCED BY EROSION OF SURROUNDING rences. Wood is substance

STRATA, GRAND JUNCTION, COLORADO.
which more commonly than

(Photo by H. Wm. Menke.)
any other petrifies, and its
form and structure are often perfectly pre-

more commonly in clays and may be made served. In petrified wood each particle up of carbonate of lime, iron pyrite or other of organic matter has been replaced by a minerals. They are formed in place in the particle of mineral matter, and thus the clay bed or other stratum by the tendency change has been made complete. The tis

which their mineral substance has had to sues of dead animals also sometimes turn to

draw together from among the surroundthe form of fat known as adipocere, which ing strata. These concretions usually take may be preserved for a longer or shorter ovoidal forms, but may be cylindrical or very time, and the tissues of plants may become irregular and may be compact or hollow. carbonized to form coal, but these include Sometimes after being forined, they crack practically all the petrifactions possible. open and the cracks become filled with anThe human body has never been preserved other mineral of different color or hardin Nature in any form maintaining its sub ness,

both. Such, especially after stance and outline as in life, and all pur- weathering, often assume very grotesque ported instances of such an

occurrence forms, whose origin would be puzzling are fictitious. In a dry climate the tissues were not one able to refer them to concremay desiccate upon the bones so as to be tions.

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or

518

GREAT BRITAIN.--There was great re home as invalids (the great majority recov-
joicing in Great Britain and throughout the ering). The total number of deaths in
Empire over the close of the Boer war. South Africa was 21,942, as indicated in
Thanksgiving services were held in St. the following table:
Paul's Cathedral and in many churches.

Officers. Men.

Killed in action King Edward congratulated Lord Kitch

5,256 Died of wounds

183 1,835 ener, who received a Parliamentary grant of

Died in captivity ,{50,000 in appreciation of his success in

5 97 conducting the war and in concluding the

Died of disease

339 12,911 Accidental deaths

27 771 peace negotiations.

By the middle of June all, or nearly all, of the fighting burghers, some 16,600 (11,225

Totals ....

.1,072 20,870 in the Transvaal and 5,395 in Orange River

Of invalids sent home who died there
Colony), had surrendered. Generals Botha, were 1,580, making the number of deaths

in all 23,522. Casualties reported in June
are not included in these figures.

The cost of the war in money, including
the estimates for the year ending March 31,
1903, is about £222,000,000 ($1,100,000,-
000). Of this sum £159,000,000 is bor-
rowed. The increase of taxation in the
United Kingdom on account of the war is
£34,000,000 for the current year; and of
this the increase of the income tax is said
to be £17,600,000. There has been much
opposition to the corn tax, and by some it is
said to be doomed. However, the govern-
ment is slow to abandon it or hold out
hopes of its speedy abolition, notwithstand-
ing the free trade leanings of Sir Michael
Hicks-Beach and other ministers. The
bread tax falls heaviest upon the poor. It
means higher prices for necessaries to a
large class of working people.

Lord Milner, who is High Commissioner for South Africa, took the oath of office as British governor of the Transvaal, on June 22.

The American shipping trust has caused Town Governor Woodroof, with Mrs. Woodroof, entertajaing a party of Americans at the Ascot Races

much alarm, not only in Great Britain, but (From a photograph taken for THE WORLD TO-Day by N.

in France and Germany. Lazarnick.)

Elaborate preparations for the coronation

were made, but owing to the King's severe De Wet and De la Rey were thanked by illness it Kitchener for their zealous efforts to pro- While his life hung in the balance, not only

indefinitely postponed. mote harmony and good-feeling among the his subjects, but Americans and the people Boers, Preparations were at once made for of other nations waited in anxious suspense, the return of Boer prisoners. The total fearing the worst.

The crisis was reached number of prisoners, as stated by Mr.

on the day set for the coronation, June 26. Brodrick in the House of Commons

It was successfully passed, and Edward's (June 3), was 25,555, distributed as fol

recovery was therefore regarded as possilows: Cape Colony, 1,055 burghers; Natal, ble and even probable. His illness brought 855; St. Helena, 5,679; Bermuda, 4,543;

out forcibly the fact that Britons the world Ceylon, 4.939: India, 8,484. The casualties on the Boer side are not

over are strongly attached to their sover

eign. known. The casualties of the British, leported up to June 1, 1902, amounted to 97,- loss estimated at $21,000,000 to the insur

The King's death would have brought a 477, including 75,430 men and officers Sent

ance companies of England. The policies

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AMERICANS IN LONDON.

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